The Effect of Molybdate on Corrosion Behaviour of AISI 316Ti Stainless Steel in Chloride Environment

Authors: Viera Zatkalíková, Lenka Markovičová, Aneta Tor-Swiatek

Abstract:

The effect of molybdate addition to chloride environment on resistance of AISI 316Ti stainless steel to pitting corrosion was studied. Potentiodynamic polarisation tests were performed in 1 M and 0.1 M chloride acidified solutions with various additions of sodium molybdate at room temperature. The presented results compare the effect of molybdate anions on quality of passive film (expressed by the pitting potential) in both chloride solutions. The pitting potential increases with the increase inhibitor concentration. The inhibitive effect of molybdate ions is stronger in chloride solution of lower aggressiveness (0.1M).

Keywords: AISI 316Ti steel, molybdate inhibitor, pitting corrosion, pitting potential, potentiodynamic polarization.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1109313

References:

[1] Z. Szklarska – Smialowska, Pitting and crevice corrosion, Houston: Nace, 2005, p. 590.
[2] Z. Szklarska – Smialowska, Pitting Corrosion of Metals, Houston: Nace, 1986, p. 281.
[3] T. Liptáková, Bodová korózia nehrdzavejúcich ocelí (Pitting corrosion of stainless steels), Žilina: EDIS - Žilinská univerzita, 2009, p. 67.
[4] V. Číhal, Korozivzdorné oceli a slitiny (Stainless Steels and Alloys), praha: Academia, 1999, p. 437.
[5] G. O. Ilevbare, G. T. Burstein, “The inhibition of pitting corrosion of stainless steels by chromate and molybdate ions” in Corrosion Science, vol. 45, pp. 1545-1569, 2003.
[6] S. A. M. Refaey, S. S. Abd El-Rehim, F. Taha, M. B. Saleh and R. A. Ahmed, “Inhibition of chloride localized corrosion of mild steel by PO4 3- , CrO4 2-, MoO4 2-, and NO2 - anions” in Applied Surface Science, vol. 158, pp. 190–196, 2000.
[7] F. Eghbali, M. H. Moayed, A. Davoodi and N. Ebrahimi, “Critical pitting temperature (CPT) assessment of 2205 duplex stinless steel in 0.1 M NaCl at various molybdate concentrations” in Corrosion Science, vol. 53, pp. 513-522, 2011.
[8] W. J. Tobler, S. Virtanen, “Effect of Mo species on metastable pitting of Fe18Cr alloys – a current transient analysis” in Corrosion Science, vol. 45, pp. 1585-1607, 2003.
[9] C. R. Alentejano, I. V. Aoki, “Localized corrosion inhibition of 304 stainless steel in pure water by oxyanions tungstate and molybdate” in Electrochim. Acta, vol. 49, pp. 2779-2785, 2004.
[10] N. Ebrahimi, M. H. Moayed and A. Davoodi, “Critical pitting temperature dependence of 2205 duplex stainless steel on dichromate ion concentration in chloride medium”, in Corrosion Science, vol. 53, pp. 1278-1287, 2011.
[11] H. A. El Dahan, “Pitting corrosion inhibition of 316 stainless steel in phosphoric acid-chloride solutions”, in Journal of Materials Science, vol. 34, pp. 851-857, 1999.
[12] Y. Zuo, H. Wang, J. Zhao and J. Xiong, “The effects of some anions on metastable pitting of 316L stainless steel” in Corrosion Science, vol. 44, pp. 13-24, 2002.
[13] V. Zatkalíková, Bodová korózia ocele AISI 316Ti pri rôznych prevádzkových podmienkach (Pitting corrosion of AISI 316Ti at various operating conditions), PhD Thesis, Žilina: ŽU v Žiline, 2008, p. 77.
[14] http://www.italinox.sk/ (15. 3. 2015).
[15] A. Pardo, M. C. Merino, A. E Coy, F. Viejo, M. Carboneras and R. Arrabal, “Influence of Ti, C and N concentration on the intergranular corrosion behavior of AISI 316Ti and 321 stainless steels” in Acta Materialia, vol. 55, pp. 2239-2251, 2007.